1. Field of the Invention
The present invention relates to an image forming apparatus such as a printer or a copying machine that performs image formation using an electrophotographic system or the like.
2. Description of the Related Art
Image forming apparatuses execute calibration in order to maintain the quality of images that they form. In Japanese Patent Laid-Open No. 62-296669 and No. 63-185279, image quality stability is improved by forming a specific test pattern on a recording material, reading an image of the formed test pattern, and feeding back the read result to an image formation condition. Furthermore, Japanese Patent Laid-Open No. 08-287217 discloses that an image formation condition is changed according to the recording material in order to maintain image quality with arbitrary recording materials.
When calibration for tone correction has been performed using a certain recording material, and an image formation condition has been determined for that recording material, if the image formation condition is changed thereafter using another recording material, there are cases where, depending on the recording material, the setting exceeds the permitted performance of the image forming apparatus. Specifically, in the case where a recording material α is used in calibration for tone correction, and there is a recording material β for which the output density is lower when using the same toner amount, the image formation condition needs to be changed for the recording material β such that the toner amount is higher. However, if that toner amount exceeds the design range of the image forming apparatus, it is possible for image defects to appear when performing transfer to the recording material β and fixing processing. It is therefore necessary to take measures such as limiting the types of recording materials used in calibration for tone correction to specific types.